package com.sky.aop;

import com.sky.annotation.AutoFill;
import com.sky.constant.AutoFillConstant;
import com.sky.context.BaseContext;
import com.sky.enumeration.OperationType;
import lombok.extern.slf4j.Slf4j;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.Signature;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.Pointcut;
import org.aspectj.lang.reflect.MethodSignature;
import org.springframework.stereotype.Component;

import java.lang.reflect.Method;
import java.time.LocalDateTime;

@Aspect
@Component
@Slf4j
public class AutoFillAspect {
/**
 * 定义切入点
 */
@Pointcut("execution(* com.sky.mapper.*.*(..))&&@annotation(com.sky.annotation.AutoFill)")
public void autoFillPointcut(){}

    /**
     * 前置通知，在执行sql语句前先进行赋值
     */
    @Before(("autoFillPointcut()"))
    public void autoFill(JoinPoint joinPoint) {
        /*1.获取被拦截方法的数据库操作类型(insert还是update)*/
        //获取方法签名
        MethodSignature signature = (MethodSignature)joinPoint.getSignature();
        AutoFill autoFill = signature.getMethod().getAnnotation(AutoFill.class);
        OperationType operationType = autoFill.value();

        /*获取到当前被拦截的方法的参数--实体对象(employee)*/
        Object[] args = joinPoint.getArgs();
        if (args==null || args.length==0){
            return;
        }
        Object entity = args[0];

        /*准备数据*/
        LocalDateTime now = LocalDateTime.now();
        Long currentId = BaseContext.getCurrentId();

        /*根据当前不同的操作类型，为对应的属性通过反射来赋值*/
        if (operationType==OperationType.INSERT){
            try {
                //相当于创建一个方法
                Method setCreateTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_CREATE_TIME, LocalDateTime.class);
                Method setCreateUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_CREATE_USER, Long.class);
                Method setUpdateTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_TIME, LocalDateTime.class);
                Method setUpdateUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_USER, Long.class);

                //相当于执行方法
                setCreateTime.invoke(entity, now);
                setCreateUser.invoke(entity, currentId);
                setUpdateTime.invoke(entity, now);
                setUpdateUser.invoke(entity, currentId);
            } catch (Exception e) {
                throw new RuntimeException(e);
            }

        } else if (operationType == OperationType.UPDATE) {
            try {
                Method setUpdateTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_TIME, LocalDateTime.class);
                Method setUpdateUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_USER, Long.class);

                setUpdateTime.invoke(entity, now);
                setUpdateUser.invoke(entity, currentId);
            } catch (Exception e) {
                throw new RuntimeException(e);
            }
        }
    }
}
